On this particular car, the problem is likely the oil cooler. Check at the oil filter housing. I think that your car has a sheet metal oil cooler mounted on the oil fitler extension housing just forward of the oil filter. It should have two water lines attached. These have a history of developing leaks - it may simply need to be replaced. You can remove it and perform a pressure test on it. If you have the older style cooler, there will be a cast piece there with OIL lines vice the sheet metal piece with WATER lines. The earlier cooler adapters have no water interface so cannot leak water, but do develop oil leaks from worn O-rings.